CVE-2025-40779 (GCVE-0-2025-40779)

Vulnerability from cvelistv5 – Published: 2025-08-27 20:23 – Updated: 2025-11-04 21:10
VLAI
Title
Kea crash upon interaction between specific client options and subnet selection
Summary
If a DHCPv4 client sends a request with some specific options, and Kea fails to find an appropriate subnet for the client, the `kea-dhcp4` process will abort with an assertion failure. This happens only if the client request is unicast directly to Kea; broadcast messages do not cause the problem. This issue affects Kea versions 2.7.1 through 2.7.9, 3.0.0, and 3.1.0.
Severity
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
SSVC
Exploitation: none Automatable: yes Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2025-08-28 14:07 UTC
CWE
  • CWE-476 - NULL Pointer Dereference
Assigner
References
Impacted products
Vendor Product Version CPE status
ISC Kea Affected: 2.7.1 , ≤ 2.7.9 (custom)
Affected: 3.0.0
Affected: 3.1.0
Unaffected: 2.6.0 , ≤ 2.6.4 (custom)
guessed Create a notification for this product.
Date Public
2025-08-27 00:00
Credits
ISC would like to thank the following for bringing this vulnerability to our attention: * Jochen M. * Martin Dinev, Trading212 * Ashwani Kumar, Post Graduate Institute of Medical Education & Research, Chandigarh, India * Bret Giddings, University of Essex * Florian Ritterhoff, Munich University of Applied Sciences
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